明渠弯道几何形态对水动力特性的影响研究OA

To investigate the influence laws of the width-to-depth ratio and the radius-to-width ratio on the hydrodynamic characteristics of open-channel bends,this study established a three-dimensional numerical model based on the RNG k-ε turbulence model and the volume of fluid(VOF)free surface tracking method.Numerical simulations of bend flow under four width-to-depth ratios and four radius-to-width ratios were conducted,with a focus on analyzing hydrodynamic characteristics such as water surface profiles,velocity distribution,secondary flows,and bend separation flows.The results indicate that the flow turbulence characteristics intensify as the width-to-depth ratio or radius-to-width ratio decreases.With the reduction of these ratios,flow redistribution becomes increasingly significant,circulation strength strengthens,and the probability of flow separation in bends increases.For the U-shaped bends with small width-to-depth and radius-to-width ratios simulated in this study,the critical conditions for flow separation are identified as a width-to-depth ratio of 1.5 and a radius-to-width ratio of 1.0.